Core-Plus Mathematics is a high school mathematics program consisting of a four-year series of print and digital student textbooks and supporting materials for teachers, developed by the Core-Plus Mathematics Project (CPMP) at Western Michigan University, with funding from the National Science Foundation. Development of the program started in 1992. The first edition, entitled Contemporary Mathematics in Context: A Unified Approach, was completed in 1995. The third edition, entitled Core-Plus Mathematics: Contemporary Mathematics in Context, was published by McGraw-Hill Education in 2015. Core-Plus Mathematics is a high school mathematics program consisting of a four-year series of print and digital student textbooks and supporting materials for teachers, developed by the Core-Plus Mathematics Project (CPMP) at Western Michigan University, with funding from the National Science Foundation. Development of the program started in 1992. The first edition, entitled Contemporary Mathematics in Context: A Unified Approach, was completed in 1995. The third edition, entitled Core-Plus Mathematics: Contemporary Mathematics in Context, was published by McGraw-Hill Education in 2015. The first edition of Core-Plus Mathematics was designed to meet the curriculum, teaching, and assessment standards from the National Council of Teachers of Mathematics and the broad goals outlined in the National Research Council report, Everybody Counts: A Report to the Nation on the Future of Mathematics Education. Later editions were designed to also meet the American Statistical Association Guidelines for Assessment and Instruction in Statistics Education (GAISE) and most recently the standards for mathematical content and practice in the Common Core State Standards for Mathematics (CCSSM). The program puts an emphasis on teaching and learning mathematics through mathematical modeling and mathematical inquiry. Each year, students learn mathematics in four interconnected strands: algebra and functions, geometry and trigonometry, statistics and probability, and discrete mathematical modeling. The program originally comprised three courses, intended to be taught in grades 9 through 11. Later, authors added a fourth course intended for college-bound students. The course was re-organized around interwoven strands of algebra and functions, geometry and trigonometry, statistics and probability, and discrete mathematics. Lesson structure was updated, and technology tools, including CPMP-Tools software was introduced. The course was aligned with the Common Core State Standards (CCSS) mathematical practices and content expectations. Expanded and enhanced Teacher's Guides include a CCSS pathway and a CPMP pathway through each unit. Course 4 was split into two versions: one called Preparation for Calculus, for STEM-oriented students, and an alternative course, Transition to College Mathematics and Statistics (TCMS), for college-bound students whose intended program of study does not require calculus. Project and independent evaluations and many research studies have been conducted on Core-Plus Mathematics, including content analyses, case studies, surveys, small- and large-scale comparison studies, research reviews, and a longitudinal study. There are multiple research studies and evaluations in which students using Core-Plus Mathematics performed significantly better than comparison students on assessments of conceptual understanding, problem solving, and applications, and results were mixed for performance on assessments of by-hand calculation skills. Some of these studies were funded by the National Science Foundation, the same organization that funded the development of Core-Plus Mathematics program. A three-part study of Core-Plus Mathematics and more conventional curricula were reported by researchers at the University of Missouri. The research was conducted as part of the Comparing Options in Secondary Mathematics: Investigating Curricula project, supported by the National Science Foundation under REC-0532214. The research was reported in the March and July 2013 issues of the Journal for Research in Mathematics Education and in the December 2013 issue of the International Journal of Science and Mathematics Education. The three studies examined student achievement in schools in 5 geographically dispersed states. The first study involved 2,161 students in 10 schools in first-year high school mathematics courses, the second study involved 3,258 students in 11 schools in second-year mathematics courses, and the third study involved 2,242 students in 10 schools in third-year mathematics courses. Results in the first study showed that Core-Plus Mathematics students scored significantly higher on all three end-of-year outcome measures: a test of common objectives, a problem solving and reasoning test, and a standardized achievement test. Results in the second study showed that Core-Plus Mathematics students scored significantly higher on a standardized achievement test, with no differences on the other measures. Results in the third study showed that Core-Plus Mathematics students scored significantly higher on a test of common objectives, with no differences on the other measure.